An error occurred during installation of assembly component

Hello Everybody,

I've been having the same problem for a very long time. I'm trying to install iTunes for my iPod, but these messages keep on coming up and cancelling the installation:

- The Windows Installer Service could not be accessed (somehow solved today)
- There is a problem with this Windows Installer Package. A program required for this install to complete could not be run. Contact your support personnel or package vendor. (I managed to solve this)
- An error occurred during installation assembly component. <-- this is my problem. I don't know how long I'm already looking for a solution for this problem, but nothing seems to work. I have already done a full virus- and anti-malware scan.

So I was hoping that you guys would come with the solution for my problem?

Kind Regards,
VistaExplorer

P.S. I tried to copy iTunes from my brother on a USB-stick to my laptop, but that doesn't help either.